The Importance of Protein in Leaf Selection of Folivorous Primates

Protein limitation has been considered a key factor in hypotheses on the evolution of life history and animal communities, suggesting that animals should prioritize protein in their food choice. This contrasts with the limited support that food selection studies have provided for such a priority in nonhuman primates, particularly for folivores. Here, we suggest that this discrepancy can be resolved if folivores only need to select for high protein leaves when average protein concentration in the habitat is low. To test the prediction, we applied meta-analyses to analyze published and unpublished results of food selection for protein and fiber concentrations from 24 studies (some with multiple species) of folivorous primates. To counter potential methodological flaws, we differentiated between methods analyzing total nitrogen and soluble protein concentrations. We used a meta-analysis to test for the effect of protein on food selection by primates and found a significant effect of soluble protein concentrations, but a non-significant effect for total nitrogen. Furthermore, selection for soluble protein was reinforced in forests where protein was less available. Selection for low fiber content was significant but unrelated to the fiber concentrations in representative leaf samples of a given forest. There was no relationship (either negative or positive) between the concentration of protein and fiber in the food or in representative samples of leaves. Overall our study suggests that protein selection is influenced by the protein availability in the environment, explaining the sometimes contradictory results in previous studies on protein selectio

Ets1 Induces Dysplastic Changes When Expressed in Terminally-Differentiating Squamous Epidermal Cells

BACKGROUND: Ets1 is an oncogene that functions as a transcription factor and regulates the activity of many genes potentially important for tumor initiation and progression. Interestingly, the Ets1 oncogene is over-expressed in many human squamous cell cancers and over-expression is highly correlated with invasion and metastasis. Thus, Ets1 is believed to mainly play a role in later stages of the oncogenic process, but not early events. METHODOLOGY/PRINCIPAL FINDINGS: To better define the role of Ets1 in squamous cell carcinogenesis, we generated a transgenic mouse model in which expression of the Ets1 oncogene could be temporally and spatially regulated. Upon Ets1 induction in differentiating cells of stratified squamous epithelium, these mice exhibited dramatic changes in epithelial organization including increased proliferation and blocked terminal differentiation. The phenotype was completely reversed when Ets1 expression was suppressed. In mice where Ets1 expression was re-induced at a later age, the phenotype was more localized and the lesions that developed were more invasive. Many potential Ets1 targets were upregulated in the skin of these mice with the most dramatic being the metalloprotease MMP13, which we demonstrate to be a direct transcriptional target of Ets1. CONCLUSIONS/SIGNIFICANCE: Collectively, our data reveal that upregulation of Ets1 can be an early event that promotes pre-neoplastic changes in epidermal tissues via its regulation of key genes driving growth and invasion. Thus, the Ets1 oncogene may be important for oncogenic processes in both early and late stages of tumor development

Quantitative effects of enhanced CO2 on jasmonic acid induced plant volatiles of lima bean (Phaseolus lunatus L.)

Globally rising CO2 has been predicted to affect plant biochemistry and in consequence the interaction of plants with multiple associated organisms. While CO2 mediated effects on nutritive compounds and direct anti-herbivore defenses appear to be well studied for many plant species, the importance of altered atmospheric CO2 concentrations on indirect defenses is only little understood. In this study, we analyzed the effects of enhanced CO2 on the release of volatile organic compounds (VOCs) using jasmonic acid (JA) as a natural hormone-like inductor. We cultivated lima bean plants (Phaseolus lunatus L.) under different CO2 concentrations (ambient, 500, 700, and 1000 ppm) and quantified the release of VOCs using GC-MS. The total release of VOCs significantly increased in response to higher CO2 concentrations. However, the quantitative emission of individual compounds was differently affected. Nine out of twelve VOCs were released at significantly higher levels (cis-3-hexenylacetate, cis-ocimene, linalool, cis-3-hexenyl butyrate, methyl salicylate, cis-jasmone, β-caryophyllene, trans-geranylacetone, and methyl jasmonate) at enhanced CO2, whereas two were not affected (2-ethylhexan-1-ol, cis-3-hexenyl isovalerate) and the release of indole decreased. Shifts in VOCs release under elevated CO(2) likely affect efficacy of plants' resistance to herbivores, as a range of the affected compounds are of central importance in defense-associated plant-plant and within-plant signaling. Given the importance of plant-herbivore interactions in terrestrial ecosystems, CO2 mediated changes in defense-associated VOCs might have implications on agricultural and natural ecosystem functions

The Relationship Between ACGME Duty Hour Requirements and Performance on the American Board of Emergency Medicine Qualifying Examination

Background  In 2003, the Accreditation Council for Graduate Medical Education (ACGME) instituted requirements that limited the number of hours residents could spend on duty, and in 2011, it revised these requirements. Objective  This study explored whether the implementation of the 2003 and 2011 duty hour limits was associated with a change in emergency medicine residents\u27 performance on the American Board of Emergency Medicine (ABEM) Qualifying Examination (QE). Methods  Beginning with the 1999 QE and ending with the 2014 QE, candidates for whom all training occurred without duty hour requirements (Group A), candidates under the first set of duty hour requirements (Group C), and candidates under the second set of duty hour requirements (Group E) were compared. Comparisons included mean scores and pass rates. Results  In Group A, 5690 candidates completed the examination, with a mean score of 82.8 and a 90.2% pass rate. In Group C, 8333 candidates had a mean score of 82.4 and a 90.5% pass rate. In Group E, there were 1269 candidates, with a mean score of 82.5 and an 89.4% pass rate. There was a small but statistically significant decrease in the mean scores (0.04, P \u3c .001) after implementation of the first duty hour requirements, but this difference did not occur after implementation of the 2011 standards. There was no difference among pass rates for any of the study groups (χ2 = 1.68, P = .43). Conclusions  We did not identify an association between the 2003 and 2011 ACGME duty hour requirements and performance of test takers on the ABEM QE

Delaying the American Board of Emergency Medicine Qualifying Examination Is Associated With Poorer Performance

Objectives The initial step in certification by the American Board of Emergency Medicine (ABEM) requires passing a multiple-choice-question qualifying examination. The qualifying examination is typically taken in the first year after residency training. This study was undertaken to determine if a delay in taking the qualifying examination is associated with poorer performance. The authors also examined the relationship between in-training examination scores and qualifying examination scores. Methods This was a pooled time-series cross-section study. Primary measurements were initial qualifying examination scores, the timing of the qualifying examination, and in-training examination scores. The three groups, based on qualifying examination timing, were immediate, 1-year delay, and ≥2-year delay. In-training examination scores were analyzed to determine the relationship between intrinsic ability, examination timing, and qualifying examination scores. For analysis, a generic pooled ordinary least-squares dummy variable model with robust standard errors was used. A pre hoc level of significance was determined to be α \u3c 0.01. Results There were 16,353 qualifying examination test administrations between 2000 and 2012. In-training examination scores were positively correlated with qualifying examination scores (p \u3c 0.001). The group pass rates were 98.9% immediate, 95.6% 1-year delay, and 86.6% ≥2-year delay. After controlling for in-training examination scores, delay taking the qualifying examination of 1 year was associated with a decrease in score of –0.6 (p = 0.003). A delay in taking the qualifying examination ≥2 years was associated with a decrease in score of –2.5 points (p \u3c 0.001). Conclusions After accounting for innate ability using in-training examination scores, delay taking the qualifying examination was associated with poorer performance. This effect was more pronounced if the delay was ≥2 years

Association between the American Board of Emergency Medicine Oral Certifying Examination and Future State Medical Board Disciplinary Actions.

OBJECTIVES: The American Board of Emergency Medicine (ABEM) requires a written examination (the Qualifying Examination) followed by the Oral Certifying Examination (OCE) to obtain ABEM certification. Maintaining ABEM certification is associated with fewer state medical board (SMB) disciplinary actions. We sought to determine the association between poor initial performance on the OCE and subsequent severe SMB disciplinary action. METHODS: We included physicians who completed US categorical emergency medicine residencies in 2016 and earlier. We classified OCE performance as good (passed on first attempt) and poor (never passed or required \u3e 1 attempt to pass). We obtained data on physician SMB disciplinary actions from the National Practitioner Data Bank that were limited to actions that denied licensure or altered the status of a medical license (eg, suspension). We determined the association between poor OCE performance and subsequent severe SMB disciplinary action. RESULTS: Of 34,871, 93.5% passed the OCE on the first attempt, 6.1% required multiple attempts, and 0.3% never passed. Of the physicians (93.5%) with good OCE performance, 1.0% received a severe SMB action. Among physicians with poor OCE performance, 2.3% received a severe action; and of those who never passed, 1.7% received a severe action (Table 1). Poor OCE performance was associated with an increased odds of severe SMB disciplinary action (OR 2.21, 95% CI: 1.57-3.12). CONCLUSION: Physicians with poor OCE performance exhibited higher odds of experiencing a subsequent severe SMB disciplinary action. The OCE may have utility as a predictor of future professionalism or clinical performance

The Relationship Between ACGME Duty Hour Requirements and Performance on the American Board of Emergency Medicine Qualifying Examination

Background  In 2003, the Accreditation Council for Graduate Medical Education (ACGME) instituted requirements that limited the number of hours residents could spend on duty, and in 2011, it revised these requirements. Objective  This study explored whether the implementation of the 2003 and 2011 duty hour limits was associated with a change in emergency medicine residents\u27 performance on the American Board of Emergency Medicine (ABEM) Qualifying Examination (QE). Methods  Beginning with the 1999 QE and ending with the 2014 QE, candidates for whom all training occurred without duty hour requirements (Group A), candidates under the first set of duty hour requirements (Group C), and candidates under the second set of duty hour requirements (Group E) were compared. Comparisons included mean scores and pass rates. Results  In Group A, 5690 candidates completed the examination, with a mean score of 82.8 and a 90.2% pass rate. In Group C, 8333 candidates had a mean score of 82.4 and a 90.5% pass rate. In Group E, there were 1269 candidates, with a mean score of 82.5 and an 89.4% pass rate. There was a small but statistically significant decrease in the mean scores (0.04, P \u3c .001) after implementation of the first duty hour requirements, but this difference did not occur after implementation of the 2011 standards. There was no difference among pass rates for any of the study groups (χ2 = 1.68, P = .43). Conclusions  We did not identify an association between the 2003 and 2011 ACGME duty hour requirements and performance of test takers on the ABEM QE